<input id="input" placeholder="City">
<script>
// Make sure that the suggested value is not removed when some JavaScript
// removes the placeholder attribute. Also make sure that the placeholder is not
// in visible mode at that point.
internals.setSuggestedValue(input, 'Springfield');
document.getElementById("input").placeholder = "";
</script>
<style>
:placeholder-shown {
background-color: red;
}
</style>